What common function does a snapshot serve in a virtual machine environment?

A snapshot in a virtual machine environment serves the important function of capturing the current state of a virtual machine (VM) for future restoration. This means that when a snapshot is taken, it saves the VM's current disk state, memory state, and the virtual machine settings at that specific point in time. This capability is invaluable for system administrators as it allows them to revert the VM back to that captured state if needed. For example, if a VM encounters issues after an update or new software installation, the administrator can restore the VM to the state recorded in the snapshot, thus minimizing downtime and potential data loss.

The other choices refer to functions that do not align with the primary utility of snapshots. While creating complete duplicates or backups of VMs is essential, that is typically done through separate backup solutions and not snapshots. Snapshots do not serve to increase storage capacity; rather, they can potentially consume additional storage space as they retain the state of the VM when they were taken. Lastly, optimizing network connectivity is not a function of snapshots, which are primarily focused on the VM's state rather than its networking configuration.